Brahmin (ˈbrɑːmɪn; brāhmaṇa) is a varna as well as a caste within Hindu society. In the Vedic- and post-Vedic Indian subcontinent, Brahmins were designated as the priestly class, serving as priests (purohit, pandit, or pujari) and spiritual teachers (guru or acharya). The other three varnas are the Kshatriya, Vaishya, and Shudra. The traditional occupation of Brahmins is that of priesthood at Hindu temples or at socio-religious ceremonies, and the performing of rite of passage rituals such as solemnising a wedding with hymns and prayers. Traditionally, Brahmins are accorded the highest ritual status of the four social classes. In practice, Indian texts suggest that some Brahmins historically also became agriculturalists, warriors, traders, and had also held other occupations in the Indian subcontinent. Purusha Sukta The earliest inferred reference to "Brahmin" as a possible social class is in the Rigveda, occurs once, and the hymn is called Purusha Sukta. According to a hymn in Mandala 10, Rigveda 10.90.11-2, Brahmins are described as having emerged from the mouth of Purusha, being that part of the body from which words emerge. The Purusha Sukta varna verse is now generally considered to have been inserted at a later date into the Vedic text, possibly as a charter myth. Stephanie Jamison and Joel Brereton, a professor of Sanskrit and Religious studies, state, "there is no evidence in the Rigveda for an elaborate, much-subdivided and overarching caste system", and "the varna system seems to be embryonic in the Rigveda and, both then and later, a social ideal rather than a social reality". Yajna According to Kulkarni, the Grhya-sutras state that Yajna, Adhyayana (studying the vedas and teaching), dana pratigraha (accepting and giving gifts) are the "peculiar duties and privileges of brahmins". The term Brahmin in Indian texts has signified someone who is good and virtuous, not just someone of priestly class. Patrick Olivelle states that both Buddhist and Brahmanical literature repeatedly define "Brahmin" not in terms of family of birth, but in terms of personal qualities.